This invention relates to a novel resinous composition containing an acrylic polymer having a plurality of alicyclic epoxide functions. The composition may be cured or crosslinked through the cationic polymerization of the epoxide function and is useful as a resinous component of coating compositions, sealants, potting or casting compositions and the like.
Cationic polymerization of epoxy resins using a cationic polymerization initiator is well-known. Usable initiators include Lewis acids, Friedel-Crafts catalyst, boron trifluoride-ether complex, photodegradable onium salts (S, Se, Te), diallyl iodonium salts and the like.
Epoxy resins or polymers used heretofore for this purpose are limited to glycidyl ether or ester epoxy resins, typically bishenol A epoxy resins, and homo- and copolymers of glycidyl acrylate or methacrylate (hereinafter collectively referred to as "(meth)acrylate"). Cation polymerization of these glycidyl epoxy resins normally requires heating.
We have now found that acrylic polymers having a plurality of alicyclic epoxide functions are more sensitive to the cationic polymerization than glycidyl epoxy resins in the presence of a proton-donating cationic polymerization initiator and therefore may be cured even at room temperature. The present invention has its basis on this finding.